Polyphenylene sulfide(PPS) is super-engineering plastic used for various industrial applications due to its outstanding thermal properties. Here we report a PPS composite, which has high thermal conductivity, containing multi walled carbon nanotubes (MWCNT) and Aluminum nitride (AlN) as thermally conductive filler. For using low filler concentration, core-shell fabrication is introduced. Core-shell fabrication is a method that the composite is prepared by the particle coating method into polymer pellets. Melt mixing fabrication needs high filler concentration for high thermal property, whereas the introduced method shows that the consecutive connection of filler particles via the surface of pellets enhances thermal conductivity. In addition, AlN filler on the surface of pellets blocks electron conduction and thus it is possible to apply on electronic components. The results of this study were investigated by FT-IR, SEM, C-therm TCi, TGA, and UTM.